Geologic Time Scale

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Across
  1. 5. A scientist that studies fossils
  2. 7. this era consisted of one-celled animals, bacteria, and jellyfish
  3. 9. saying someone is younger than their father is using _____ age
  4. 10. 65.5 million years ago to present day eon
Down
  1. 1. index ___ are also used to determine the age of rocks
  2. 2. A scientist that studies the Earth's crust
  3. 3. a rock is younger because it is ____ between multiple other layers
  4. 4. the law of ___ is a law used when a layer is above a layer, making the bottom layer older than the upper layer
  5. 6. precisely finding a fossil's age
  6. 8. Earth's first era